This invention relates to icemakers for household refrigerators and more particularly to ice makers that adjust the fill time based upon a sensed level of filling of the ice tray.
Conventional ice makers typically provide an ice tray including a plurality of compartments to be filled with water which is frozen to form ice cubes. A water supply is typically in fluid communication with at least one of the compartments of the ice tray. Often weirs, slots or gaps are provided between adjacent compartments in the tray so that water may be introduced into one compartment and overflow into adjacent compartments.
Typically ice makers use a timer controlled valve on the water supply to determine the level of water in the compartments. This method of controlling water level requires an initial calibration of the device to achieve the desired fill level. Often the fill level may be adjusted by the user between a minimum level wherein the valve is open for a minimum time interval and a maximum level wherein the valve is open for a maximum time interval.
In some prior art devices, the timer is implemented on a disk attached to the end of a motor driven shaft of an ejector arm that rotates at a known rate. In such implementations, during an ejection cycle when the ejector arm is being rotated 360 degrees to eject the ice cubes, a contact engages a conductive strip on the disk after the ejector arm has rotated sufficiently to eject ice formed in the compartments of the tray thereby closing a circuit that opens the solenoid operated water valve. The conductive strip extends about the focus of the disk and has a length. However, the conductive strip is either non-concentrically located or varies in width so that lateral movement of the contact can cause the contact to engage and disengage the conductive strip at various points during rotation of the ejector arm. Thus, by adjusting the lateral position of the first contact, the user can control the time that the water fill valve is opened and thus adjust the level of the water in the compartments.
Unfortunately, timers alone cannot guaranty consistent fill levels. Over time, water lines tend to become corroded or clogged with mineral deposits. Additionally, water pressure may vary. These factors alter the flow rate of water into the compartments and thus the fill level of the compartments. An increase in flow rate could result in an overflow of the ice-tray allowing water to flow into the freezer compartment. A decrease in flow rate could result in smaller ice cubes and insufficient ice supply.
Thus, an ice maker that adapts to differing flow rates to maintain the fill level of the ice forming compartments would be appreciated.
According to one aspect of the disclosure, a method of producing ice comprises the steps of opening a valve for a first period of time, determining if a level of water is below a threshold value, opening the valve for a second period of time. The opening a valve for a first period of time step occurs during a first ice making cycle so that water advances from a fluid source into at least one ice forming compartment of an ice tray through the valve. The determining if a level of water is below a threshold value step occurs in at least one ice forming compartment during the first ice making cycle. A control signal is generated in response to the determining step. The opening the valve for a second period of time occurs during a second ice making cycle in response to generation of the control signal so that water advances from a fluid source into the at least one ice forming compartment of the ice tray through the valve during the second ice making cycle. The second period of time is greater than the first period of time.
According to a second aspect of the disclosure, a method of producing ice, comprises the steps of performing successive ice making cycles, determining if a size characteristic of said ice member produced during a first ice making cycle is less than a threshold value and generating a control signal in response thereto and increasing a magnitude of said water advancement period for a subsequent ice making cycle in response to generation of said control signal. Each ice making cycle includes advancing water into at least one ice forming compartment of an ice tray by opening a valve connected to a water source for a water advancement period and reducing the temperature of water within said ice tray after said water advancing step so as to cause said water located within said at least one ice forming compartment to become an ice member.
According to yet another aspect of the disclosure, an icemaker assembly comprises an ice tray, a water line, a valve, a control system, and a water level detection system. The ice tray has at least one ice forming compartment. The water line is configured to advance water from a water source to the ice tray. The valve is operable to selectively block advancement of water through the water line while an actuation signal is generated. The control system is operable to generate the actuation signal for a water advancement period. The water level detection system determines if a level of water in the at least one ice forming compartment is below a threshold value and generates a control signal in response thereto. The control system is further operable to increase a magnitude of the water advancement period in response to generation of the control signal.
According to still another aspect of the disclosure, an icemaker assembly comprises an ice tray, a water line, a valve, a control system and an ice size detector. The ice tray has at least one ice forming compartment. The water line is configured to advance water from a water source to the ice tray. The valve is operable to selectively block advancement of water through the water line while an actuation signal is generated. The control system is operable to generate the actuation signal for a water advancement period. The ice size detection system determines if a size characteristic of an ice member located in the at least one ice forming compartment is less than a threshold value and generates a control signal in response thereto. The control system is further operable to increase a magnitude of said water advancement period in response to generation of the control signal.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.
Corresponding reference characters indicate corresponding parts throughout the several views. Like reference characters tend to indicate like parts throughout the several views.